close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2112463

код для вставки
March 29, 1938..
“
s. M. HULL
‘ .
2,112,463
PUMPING MECHANISM
Filed Dec. 11, 1933
2 Sheets-Sheet 1
.
-
J'noarzzbr:
_
i March 29, 1938.
s‘. M. HULL
‘
2,1 12,463
PUMPING MECHANISM
Filed Dec. 11, 1933
3 Sheets-Sheet?
\\\
n
I
w
1
a
u
,
a
A"
,
11v
JW
gazing, MJZQZZL
I
J
I
55.‘
?wyéw
Patented Mar. 29, 1938
2,112,463
UNITED STATES ‘
PATENT OFFICE
2,112,463
PUMPING MECHANISM
Sidney M. Hull, Western Springs, 111.
Application December 11, 1933, Serial No. 701,785
3 Claims. (Cl. 23 0—79)
My invention relates to anovel form of pump
from each other; with three rotors theirv points I
ing mechanism and method thereof, and is char
of tangency will be 120° apart; while with four
acterized by the employment of a plurality of rotors, they may be distributed at each 90°
co-acting and correlatively rotating -members, around the circle. Since the rotors have their
one of the said members serving as a rotatable
centers of rotation displaced with respect to the
casing; a liquid within the said casing member center of rotation of the casing within which
and maintained in operative relationship to the they are located, it is apparent that, at the point
said members by centrifugal force; means for of tangency thereof with the interior of the
the furnishing of the fluid medium to be pumped, casing, the pockets located upon their peripheries
11 (i to the said members and for the withdrawal
will be radially submerged in a wall of liquid 10
therefrom; and driving means for producing ro
contained within the casing, While at a point
tation of the said members.
drawings, I have discovered a new principle in
180° from their points of tangency, the said pock
ets will be open to the atmosphere contained
within the casing. The radial depth of the said
the design of pumps which substantially elim
inates sliding friction between the usual rotat
radial depths of the pockets on the said rotors
As will be fully
apparent from this speci?cation and appended
liquid wall is, in practice, proportioned to the 15
ing means and the customary ?xed casing. This
and is maintained within the casing as a pe
I accomplish by substituting for the customary
ripheral layer by the centrifugal force exerted
by direct rotation and by the displaceably mount
fixed casing a rotatable casing, preferably in the
form of the common centrifuge bowl, within
which is located a rotor or rotors in rotatable
relationship thereto. While this rotor or rotors
may be driven by providing gearing means be
tween rotor and casing, or by an auxiliary driv
ing means such as an electric motor, I prefer
to effect rotation of the rotor or rotors within
the said rotatable casing by the employment of
a liquid between rotor and casing. This liquid,
traveling at substantially the same speed as the
3 0 casing, exercises a viscous drag upon the rotor
and causes rotation thereof at a speed corre
sponding to the relative diameters of rotor and
casing. It is thus evident that a “liquid gearing”
is accomplished between casing and rotor and
that the peripheral speeds of rotor and casing
at the point of operative tangency will be sub
stantially identical if the natural lag between the
two be neglected. In practicing my invention, a
number of designs may be employed to accom
40 plish the phenomena of suction and pressure
delivery, but I prefer to furnish the rotor or
rotors with a series of substantially uniformly lo
cated pockets on the periphery thereof, which
pockets are successively emptied .of and ?lled by
the liquid disposed between the rotor and the
casing. To accomplish this purpose, the rotor
ed lip located upon the outer. edge of the said
casing. The radial width of this lip is also pro
portioned with respect to the radial depth of
the said pockets and of the said liquid wall ‘to
maintain the liquid within the casing during
rotation. At the same time, however, the radial
width .of the lip is such that any substantial
excess of liquid beyond that desired for complete
?lling of the pockets ‘during rotation is thrown
by centrifugal force outside of the .bowl and
escapes into a vented housing appropriately fash
ioned around the said casing. This housing is
designed to surround the casing and to provide
a substantially tight sealing thereof from the out
side environment, being mounted, if desired, upon
the frame containing the driving means for the
said casing and provided with a sealing means
where the shaft connecting the driving means
with the casing passes therethrough. This hous
ing may also serve as a support for the axis of
rotation of the rotor or rotors and is provided
with a duct for the introduction of the ?uid to
be pumped. In addition, inlet and outlet con
nections of any suitable design may be furnished
to allow ingress of liquid to a point within the
rotating casing and for egress of any super?uity 45
thereof.
-
or rotors are mounted ,on axes independent of
Leading from the pockets radially distributed
the rotating casing, the said axes being radially
displaced with respect to the center of rotation
of the said casing. When a plurality of rotors
is employed, they may be located Within the
casing at ‘uniformly distributed points, i. e., two
on the periphery of ‘the rotor as described above
are small vents opening, from those portions of
the pockets radially innermost to the center of ' 50
rotation and leading to a vertical tubular support
upon which is mounted the said rotor. Where
rotors ‘will be displaced in such a manner that
tubular support and rotor are integral, these
vents are provided with check valves opening
radially inward to allow egress of the v?uidbeing
the points of operating tangency thereof with
55 the inside of the casing will belocated at,_1,80°
5
2 ,
‘52,112,463
pumped, from the said pockets during that por
tion of the rotation approaching the point of
tangency between rotor and casing, i. e., the
compression sector. At the same time, these
valves prevent the backward flow of the fluid.
from the tubular support peripherally outward
to the pockets during the remainder of the ro
tation, i. e., the induction portion of the cycle.
When the rotor is mounted to revolve upon a
10 ?xed tubular support, the said vents leading from
the pockets to the support remain unobstructed,
the cut-off between pockets and tubular support
being accomplished by radially slotting the said
tubular support only through a length corre
15 sponding to the said compression sector.
I am aware that many rotary pumps have been
designed where liquids have been employed as
a sealing means between rotor and casing and
for effecting displacement of the fluid to be
20 pumped from between vanes or other members
of the rotor, i. e., liquid piston'principle. In all
cases which have come to my attention, however,
a ?xed casing of circular or elliptical design has
been employed where the liquid sealing and dis
25 placing means has been caused to circulate at
comparatively high speeds.
The friction pro
duced by such a liquid sliding over the inner
surface of a ?xed casing coupled with the surging
of the liquid in some forms of design have caused
30 marked loss in efficiency in devices based on this
principle. By employing a rotating casing, such
as I contemplate, with substantially identical
peripheral speeds between casing and rotor, I
accomplish an almost perfect type of rolling en
35 gagement between casing, liquid and rotor, and
thus eliminate to a large degree the source of
inef?ciency so inherent in previous devices.
In the drawings, Fig. 1 is a horizontal, sectional
View of my pump taken on line I—I of Fig. 2
40 illustrating the eccentric relationship of the rotor
and bowl.
Fig. 2 is, a vertical, sectional view of the pump
shown in Fig. 1.
Fig. 3 is a diagrammatic plane view of a slightly
45 modi?ed form of my invention.
Fig. 4 is a detailed, vertical sectional view of
a modi?ed form of rotor and mounting therefor.
Fig. 5 is a View similar to Fig. 2 illustrating the
modi?ed form of my invention shown diagram
50 matically in Fig. 3.
Fig. 6 is a vertical section view of a further
modi?cation illustrating the geared relationship
between the rotors and bowl.
To make more apparent to those skilled in the
55 art the principles and operating relationships of
my novel design, I have caused one embodiment
of my invention to be rep-resented diagram
matically in Figures 1 and 2 of the appended
drawings, wherein Figure 2 represents an eleva
tion in vertical section of the characteristic ele
ments of my design, and Figure 1 represents a
plan view in horizontal section along line I—I of
Figure 2, looking from above. Referring initially
to the vertical section represented in Figure 2,
65 6 is a rotatable casing, preferably in the form
of a shell centrifuge bowl, mounted upon shaft 1,
which leads to the driving means for effecting
rotation. This driving means, not shown, may be
an electric motor, belt-driven pulley or other de~
70 sired means. Rotor 8 is located within casing 6
and is mounted integrally upon tubular shaft 9
which projects through the displaceably mounted
cover plate ill’ of housing It] which tightly en
closes casing 6 and is provided with a suitable
75 sealing means I I around shaft 1. Where tubular
support 9 ‘projects through housing plate [0’, a
second sealing means I2 is also provided, while
bearings l3 and Hi are suitably disposed between
tubular shaft 9 and the surrounding portion of
housing plate Hi’ to assume the vertical and
radial thrusts exerted upon the said shaft. Seal
ing means I l is not necessary when the device is
to be employed as a compressor, but in the case of
use as an exhaustion or vacuum-producing means,
it is important that sealing means II and I2 be 10
provided to operate in a substantially air-tight
manner to maintain the interior of housing II]
at the pressure existing within casing 6. Lip I5
is displaceably mounted upon the upper periphery
of casing 6 and is designed to project radially
inward to an extent su?cient to maintain the
desired radial depth of liquid within casing 6,
while at the same time lip l5 will allow any ex
cess of the said liquid to be thrown outward into
housing l0 and drained therefrom through vent 20
I6. It will be observed that rotor 8 is mounted
with its center of rotation radially displaced with
respect to the center of rotation of casing 6 to
such an extent that the periphery of rotor 8 is
closely adjacent (point of tangency) to the in 25
terior wall of casing 6 at a point in line with the
centers of rotation and to the side (left) toward
which displacement of rotor 8 occurs. Rotor 8 is
fashioned in the form of a gear having teeth 11
substantially uniformly disposed around the 30
periphery thereof and forming pockets l3 between
the said teeth. In practice, teeth I‘! are designed
not as teeth but as separating membranes having
a very narrow width at their crests to facilitate
ease of piercing the liquid wall with which they 35
engage. From their crests, these teeth increase
gradually in thickness to form pockets therebe
tween with concave inner surfaces. While teeth
I‘? form the sides of the said pockets, the ends
therof are formed by the use of face-plates i9 and
2B, which are integrally ?xed to the faces of
the rotor and extend peripherally outward to a
point flush with the external diameter of rotor
8. Where face-plates l9 and. 20 form the ends
of pockets 18 they may be built up or otherwise
fashioned on their interior surfaces to produce
concave contours in a plane at right angles to the
previously cited concave contours in order thus
to provide a pocket surface which may easily be
wiped entirely free from gas or other ?uid by the 50
liquid displacing means to be described later.
Leading from those portions of the pocket
surfaces radially nearest to the center of rotation
of rotor 8 are tubular vents 2! which connect the
said pockets to the interior of tubular support 9. 55
These vents 2| are provided with threads at their
radially exterior termini, and check valves 22 pro
vided with corresponding threads. are screwed
into vents 2|. These valves 22 are so designed
as to open inwardly and are shown in the cus
60
tomary form of ball checks, wherein the balls
are seated by centrifugal force but are prevented
from displacement into the tubular support oy
cages. A liquid which is represented by the
cross-hatched areas 23, forming a standing wall 65
within casing 6 and lip I5, is provided in a quan
tity sufficient to provide a radial thickness there
of substantially equal to the total radial depth
of pockets 18. This liquid may be water, mercury,
oil or any other suitable liquid medium and when 70
employed for the production of vacua, mercury
is to be preferred by reason of its low vapor ten
sion at ambient temperatures. If a vacuum
lower than the vapor pressure of water at the
temperature to be maintained within the device 75
3
2,112,463
' is notdesired, .water. may be .employed in this
event, or when use of the mechanism as a com
pressor is contemplated, this water may be re
plenished or changed'to elTect cooling thereof by
vsupplying a continuous stream through inlet
‘24 to casing 6. vIn the event that excess liquid
is‘thus furnished, such excess will be automatic
ally rejected around lip l5 and thrown off into
housing I 6 fromwhich it may be drained through
10 vent l6 through any‘suitable sealing means.
Turning now to rotor 8, it is evident that the
diameter thereof will be substantially smaller
than the diameter of easing 6, and to an extent
sufficient for complete clearance between the
outer periphery of teeth l1. and the interior face
of liquid 23, at a position 180° displaced from the
.point where rotor 8 and casing 6 are in close
proximity. Teeth l1 and pockets 18 are designed
toprovide a suitable depth of the said pockets
20 with respect to the diameters of rotor 8 and easing
'6 and to the radialwidth of lip l5 as well as to
the length of radial displacement between the
ing that rotation of rotor '28 is effected in a coun
ter-clockwise direction with a ‘maximum clear
ance between teeth 29 and the interior liquid
wall, as described under Figures 1 and 2 oc
curs at three o’clock and that the teeth are at
a point of substantial tangency with the interior
surface of the casing (not shown) at nine o’clock,
tubular support 25‘ is provided along its conical
face with a radial slot 33 extending in the plane
of rotation of the said rotor from approximately 10
twelve o’clock to nine o’clock. In this manner,
during the compression portion of the revolution
of rotor 28, the ?uid medium displaced by the
liquid form within pockets 38 is'given a means of
escape from the said pockets to the interior of 1.15
tubular support 25, while at the‘same time the
‘said pockets .are effectively out off from access to
the said tubular support during the remainder
of the revolution of the said rotor. In. this case,
care should be taken that the conical surface sep
:20
arating rotor 28 from support 25 is located with
relation to the depths of pockets 3i], and the
centers ‘of rotation‘of rotor 8 and casing 6 in such’ radial thickness of liquid within the rotating cas
a; manner as to allow for the use of a radial depth
of liquid 23 substantially equal to the depth of
the said pockets.
As shown, inlet 25 forms a
means of entrance for the ?uid medium being
pumped through housing plate ID’ to the interior
of easing 6 and thence at the right through the
30
clearance between teeth I‘! and liquid 23 to
pockets l8. As previously mentioned, the said
fluid medium is exhausted through vents 2| and
valves 22 to the interior of tubular shaft 9 and
thence to connection at seal l2.
CO 0
In Figure 1, as previously mentioned, is shown
the plan view and horizontal section through lines
taken at aa, looking down from above. Here,
numbers have been employed corresponding to
those used- in Figure 2 to denote identical ele
ments of design. In this ?gure, a better repre
sentation is afforded of rotor 8, contours of teeth
I‘! and of pockets l8, vents 2|, check valves 22,
casing 6, and radial thickness of liquid as repre
sented by circle 23. Circle 18 denotes the housing
surrounding casing 6, while casing 6 is represented
merely in horizontal section. A horizontal sec
tion of the tubular shaft support for rotor 8 is
denoted by 9.
In Figure 4 is represented diagrammatically
50 a modi?cation of the design shown in Figures 1
and 2. Here, in place of the integral mounting
of rotor 8 upon tubular shaft 9, with check valves
22 and vents 2! of Figure 2, tubular shaft 25 is
rigidly mounted in the housing plate denoted by
H!’ in Figure 2 and provided with anti-friction
bearings 26 and .21 immediately above and below
rotor 28.
It is assumed that rotor 28 will be pro
vided with teeth 28 and pockets 30, correspond
ing to the elements denoted by numerals I1 and
60 I8 in Figures 1 and 2, while vents 3| lead from
the radially innermost portions of the said pock
ets to the interior periphery of rotor 28. Inv this
design, with the radial and axial thrusts of rotor
28 assumed by bearings 26 and 21, it is expedi
65 em to fashion that section of a ?xed tubular sup
port 25 located between bearings 26 and 21 in the
ing to provide substantially complete displace
ment of the ?uid medium being‘ pumped, from 25
the pockets to the said conical surface.
These
various factors may be so proportioned with re
spect to their dimensions and to the radial width
of lip I5, shown in Figure 2, as to effect suf
?cient clearance between rotor 28 and the seal
in'g liquid ‘(not shown), and at the same time to
effect complete ?lling of pockets 30 and vents
is! up to the point of cut-off. It is self-evident
that the design thus illustrated in Figure 4 may
be applied to the embodiment of my invention 35
as represented in Figure 3, wherein a plurality
of rotors is employed.
Referring particularly to Figs. 3 and 5, a slight
modi?cation of my invention is shown wherein
l0” indicates a casing similar to casing ID with
in which a bowl 6” is rotatably mounted upon
shaft 1” which in turn may be supported in a
bearing structure similar to structure ll. Two
similar hollow shafts 9" protrude through cas
ing l8", said shafts being interconnected ex 45
teriorly of the casing by the conduit l2" having
a common outlet l3".
Each shaft 9" is similar
to'shaft' 25 shown in Fig. 4 and has similar frus
tro-conical bearing surfaces [4" and bearings
26" and 21". A rotor 28" is mounted upon each
of the shafts 9" and is rotatablerthereon. Each
of the rotors 28" has teeth 29” and pockets 38",
while vents 3|" lead from the radially innermost
portions of said pockets to the interior periphery
of rotor 28". A radial slot 33" is provided in F
each ‘of the tubular shafts 9” similar to the slot
33 in Fig. 3.
~
The modi?cation of my invention shown in Fig.
6 is similar in all respects to that shown in Fig.
5 with the exception that bowl 5" is positively 60
geared to rotors 28" by means of gears 28a car
ried by each of the rotors 28".
Having thus set forth the fundamental princi
ples upon. which my invention is based and the
differentiation between my invention ‘and the 65
70 noted at their junction by numeral 32 are not
prior art, and having described a number of em
bodiments of my invention with‘respect to the
diagrammatic representations thereof, a brief
description will be given of the manner of op
load-bearing, and since their proximity can be
eration characteristic of the mechanism claimed
closely adjusted and rigorously maintained by
bearings'ZS and 21, the said conical surfaces may
be accurately machined and ground to provide a
suitably small clearance therebetween. Assum
herein.
form of. a cone with the interior periphery of ro
tor 28_being fashionedas a corresponding conical
surface. Since these two conical surfaces de
75
It is a matter of common knowledge that
a liquid medium within ‘a bowl or, casing which
is, rotated at .high' speed will rapidly migrate to
the inner periphery of ‘such a casing and assume
70
4
2,112,463
a vertical position therein, thus presenting a ver
tical face normal to a line drawn radially be
tween the center of rotation and the periphery
centrifugal forces involved ‘in my device.
thermore, my invention is capable of an extreme
variation of size, it being possible to secure a free
Such a liquid when subjected
air capacity of 25 to- 30 c. f. m. with a casing di
to high speeds of revolutionv will be subjected to
high centrifugal force which causes a large in
ameter of 8", a rotor diameter of 6.5", an over
of such a casing.
crease in the viscous friction thereof and tends to
render the liquid extremely compact and dense.
In this condition its manner of behavior is more
10 analogous to a semi-?uid or plastic medium than
to the liquid state and it becomes very resistant
toward any force tending to deform its assumed
contour or location with respect to the casing
within which it is held. By the interposition of
15 a rotor or rotors as set forth above with the
axes of rotation of the said rotors non-coincident
with the axis of rotation of the liquid-containing
casing, to a point where the teeth of the said ro
tors as described under Figures 1, 2, 3 and 4 will
20 engage in the said liquid, it is apparent that the
rotation of the casing and the liquid contained
therein at high speeds will carry the rotor or
rotors with them at substantially identical pe
ripheral speeds of travel between casing and ro
25 tors.
With appropriate design of teeth and pock
ets and suitable location of the rotors with
respect to the casing, all as described above, and
with a housing surrounding the said casing for
separation thereof from the surrounding en
30 vironment and for the carrying of the supports
for the said rotors and other functioning means,
it is evident that the ?uid medium, such as a gas
existing with the said housing and also within
the said casing, will be supplied to the said pock
ets at the point where a suitable clearance is pro~
vided between rotor and interior liquid wall. As
the rotor continues to turn from this position of
clearance to a- point where the teeth provided
on its periphery engage with the interior vertical
40 liquid surface, the fluid or gaseous contents of
the said pockets will become trapped and will be
progressively compressed from this point to the
point where a clearance between rotor and cas
ing becomes so small that the liquid medium car
45 ried within the said casing will completely dis-.
all thickness of rotor 1.5", a quantity of liquid
(less than a pint) suf?cient to form a radial
thickness within the casing of approximately 1"
and a speed of 3,600 R. P. M. With diameters of
casing and rotor of 20" and 16” respectively and a
speed of 3,600 R. P. M., with a thickness of rotor of
approximately 2.5", a free-air capacity of 600
c. f. m. may be developed, while greater thick
nesses of rotor with substantially the same di
ameters will increase this free-air capacity to 15
1,000 c. f. m. or more.
When two or more rotors
are employed in conjunction with a single cas
ing, their speeds of rotation will be increased
with respect to the speed of rotation of the cas
ing in substantially the ratio of the casing di 20
ameter to the rotor diameter, and such increased
speeds will more than compensate for the re
duction in capacity due to their smaller sizes and
wastage of space. Likewise, with the rotors dis
tributed around the casing at regular intervals,
as described above, a substantially uniform bal
ance of thrust may be maintained upon the cas
ing at all times.
In describing the type of rotor with its associated
forms of teeth and pockets to be employed in the
practice of my invention, I do not wish to be lim
ited to any speci?c form of tooth pro?le. While
under certain conditions the so-called teeth may
be designed as thin sections or dividing septa, it
may be found desirable to fashion such pro?les I
in a manner corresponding to the customary gen
erated pro?ling of gear teeth, or analogous there
to. It is evident that a pro?le form of tooth may
be generated for each speci?c application and as
sociated conditions wherein the teeth during im 40
mersion into or emergence from the peripheral
liquid wall will present a surface relative to the
face of the said liquid wall in a direction substan
tially relieving same at the points in question.
While I have described the principles of my I
place the said contents of the pockets and force
invention and its manner of functioning in de
the fluid or gaseous medium substantially com
tail, and have set forth certain relationships, di
mensions and con?gurations of structural ele
pletely from the said pockets and through the
valving means shown and described under Fig
50 ures l, 2 and 4.
Following such complete dis
placement by the liquid, the teeth will again
progressively emerge from the liquid and will be
characterized by the presence of a substantially
Torricellian vacuum therein, ready for re-?lling
55 by the ?uid or gaseous medium present Within
the said housing. In this manner my device may
function very effectively as a highly efficient vac
uum pump or as a compressor with the abil
ity to produce and maintain vacua of a high order
60 when the liquid centrifugally held within the cas
ing is mercury or some other liquid medium of
low vapor pressure. It will be very evident to
those skilled! in the art that the only care neces
sary is to so adjust the length of teeth, depths
65 of pockets, location of valving or cut-off means,
spacing of rotor with respect to the casing,
and suitable control of other characteristic fea
tures described and speci?ed above, that clear
ance between rotor and liquid will occur at one
70 point of the rotation and complete ?lling of the
pockets by the said liquid at another point of ro
tation of the said rotor. That quite large pres
sures may be developed by such a pumping mech
anism rotating at speeds of 1,800 to 3,600 B. P.
75 M. will be evident from a consideration of the
ments in a manner clearly to indicate the manner
of functioning thereof, I do not wish to be
limited to such elements, dimensions, and/or
con?gurations, it being clearly understood that
my representations have been purely diagram
matic and serve only to afford those sln'lled in the
art of pump-ing mechanisms and. associated ap 55
paratus with suf?cient information to reproduce
the results of my invention. Furthermore, the
term “point of tangency” has been employed in a
purely relative sense, contact between rotor and
casing occurring either actually, in the case of 60
direct gearing, or ‘being substantially effected by
what I have chosen to term “liquid gearing”. In
all cases the expression “point of tangency” de
notes the point of minimum radial clearance be
65
tween rotor and casing.
Having thus described the characteristic fea
tures of my novel pumping mechanism, I claim:
1. A pump, comprising in combination a sta
tionary casing having an inlet therein, a rotat
ably mounted driven bowl in said casing having 70
an inlet in the upper side thereof, a ?uid in said
bowl, a rotor in said driven bowl having a plu
rality of peripheral pockets therein mounted in
eccentric relation with said driven. bowl, a hol
low axle upon which said rotor is mounted, the 75
2,112,468
said rotor having passages from said pockets to
the hollow axle, and valves in said passages.
2. A pump comprising, in combination, a sta
tionary casing having an inlet therein, a rotat
ably mounted horizontally positioned driven bowl
in said casing having an opening at one‘ side
thereof extending substantially the entire dis~
tance around the said bowl, a fluid in said bowl,
a rotor in said driven bowl having a plurality of
10 peripheral pockets therein mounted in eccentric
relation with said driven bowl, a hollow axle upon
which said rotor is mounted, the said rotor hav
ing passages from said pockets to the hollow axle,
and valves in said passages.
5
3. A pump comprising, in combination, a sta
tionary casing having an inlet therein, a rotat
ably mounted, horizontally positioned driven
bowl in said casing having an opening at one side
thereof extending substantially the entire dis
tance around the said bowl, power means for
driving said bowl, a ?uid in said bowl, a rotor in.
said driven bowl having a plurality of peripheral
pockets therein mounted in eccentric relation
with said driven bowl, a hollow axle upon which 10
said rotor is mounted, the said rotor having pas
sages from said pockets to the hollow axle, and
valves in said passages.
SIDNEY M. HULL. ,
Документ
Категория
Без категории
Просмотров
0
Размер файла
938 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа